createNullableDoubleProperty method Null safety
Short hand helper function for initializing an EmpireNullableDoubleProperty.
See EmpireProperty for propertyName usages.
Example
late final EmpireNullableDoubleProperty percentage;
percentage = createNullableDoubleProperty();
Implementation
EmpireNullableDoubleProperty createNullableDoubleProperty(
    {double? value, String? propertyName}) {
  return EmpireNullableDoubleProperty(value, this,
      propertyName: propertyName);
}